ipnat filtering exception

I am using the ipfilter built into FreeBSD 5.4 v3.4.35 (336). I just
came across a need to use a new redirect, but I don't see anything in
the Howto discussing it, which usually fixes me up.

I have this new rule:
rdr fxp0 0.0.0.0/0 port 25 -> 192.168.0.1 port 2525

This will allow all port 25 traffic starting from LAN to WAN to go to
port 2525 on a machine of my choice.

Exception 1.
Fine, but I need to make a few exceptions. For example, say I have a PC
at 192.168.5.5 that needs to be excepted. How do I keep this PC from
being redirected?

Illustration Exc1:
rdr fxp0 0.0.0.0/0 port 25 -> 192.168.0.1 port 2525, *UNLESS* source is
192.168.5.5


Exception 2.
Also, what if we contact a special server, which needs no redirection?
Say, server 192.168.0.1 port 25 traffic is legitimate, and everyone on
the LAN should receive *no* redirection for that special server?

Illustration Exc2:
*DONOT-rdr* fxp0 192.168.0.1 port 25 no matter what the source is.


Thanks,
Billy